Prophylaxis with antiviral medications reduces CMV disease and CMV-associated mortality in solid organ transplant recipients

Cytomegalovirus (CMV) is the most common virus pathogen in solid organ transplant recipients (kidney, heart, liver, lung and pancreas) being a major cause of morbidity and mortality during the first six months after transplantation. Two main strategies to prevent CMV disease have been adopted: prophylaxis of organ recipients with antiviral agents, or 'pre-emptive therapy' of organ recipients, who develop evidence of CMV infection during routine screening. This review looked at the benefits and harms of antiviral medication to prevent CMV disease in solid organ transplant recipients. Thirty four studies (3840 participants) were identified. This review shows that the antiviral medications, ganciclovir, valaciclovir and aciclovir reduced the risk of CMV disease, all-cause mortality due to reduced mortality from CMV disease, clinical disease caused by herpes simplex and herpes zoster, bacterial infections and protozoal infections. For CMV disease and mortality, the relative benefits of aciclovir, ganciclovir and valaciclovir appear consistent across recipients of heart, kidney and liver transplants. These benefits occur in both CMV positive recipients and CMV negative recipients of CMV positive organs, are irrespective of whether immunosuppression includes antilymphocyte antibody therapy and are not dependent on the time of outcome assessment. In comparison studies, ganciclovir is more effective than aciclovir and as effective as valganciclovir, which is currently the most commonly used antiviral medication to prevent CMV disease in transplant recipients. More studies are needed in lung and heart transplant recipients and to determine the optimum duration and dosage of medications for all solid organ transplant recipients.